Boffins are now even more puzzled about where high-energy cosmic rays come from after a new study showed that gamma ray bursts are probably not to blame.
Cosmic rays hitting Earth Cosmic rays hitting Earth. Credit: NSF/J. Yang
Astroboffins only had two theories about what causes cosmic rays, which regularly penetrate Earth's …

Re: Yes, but surely the more important question is

My theory

Whatever produces cosmic rays would reasonably be expected to produce copious amounts of gamma rays and neutrinos. I think what they're saying is that there's no burst of neutrinos detected that can be linked to GRBs, so they can't be the source of cosmic rays.

Useless factoid of the day: the highest energy cosmic rays consist of a proton/other atomic nucleus having the kinetic energy of a tennis ball served by a Wimbledon ace.

"chalk dust"

"Gamma ray burst" is a name for an astronomical phenomenon. These things produce large amounts of gamma rays for brief periods, hence the name. And apparently the models for how they work say that _if_ they also produce cosmic rays, then they must produce neutrinos. No neutrinos observed, therefore no cosmic rays. (Or the model is wrong, but it would take a different experiment to show that.)

So the answer to your question is 'neither'. There is a theory that says that gamma rays, neutrinos and cosmic rays may all be co-produced by a GRB and that theory is now less plausible, because the neutrinos are missing.

Only one solution...

Gamma bursts

The faint blue light ...

The faint blue light is caused when neutrinos interact with the atoms in the ice, causing electrically charged particles (electrons and/or bits of nucleus) to recoil faster than the speed of light (in the ice, where the speed of light is slower than in a vacuum). It's called Cerenkov radiation.

Still, exceeding the local speed limit causes blue lights even at subatomic scales.

long live the oh my god particle

Cosmic ray particles with even higher energies have since been observed. Among them was the Oh-My-God particle observed on the evening of 15 October 1991 over Dugway Proving Ground, Utah. Its observation was a shock to astrophysicists, who estimated its energy to be approximately 3×10^20 eV (50 J)[3]—in other words, a subatomic particle with kinetic energy equal to that of a baseball (5 ounces or 142 grams) traveling at about 100 kilometers per hour (60 mph). It was most probably a proton traveling at about (1 − 5×10−24) metres per second slower than the speed of light (approximately 0.9999999999999999999999951c), so close that in a year-long race between light and the particle, the particle would fall behind only 46 nanometers (5×10−24 light-years), or 0.15 femtoseconds (1.5×10−16 s).

Re: long live the oh my god particle

Re: long live the oh my god particle

Well, if the process was 100% efficient, the amount of energy needed is as stated in the article. It's just that we don't have a clue how to concentrate that much energy into a single particle.

Perhaps there are weakly interacting massive particles left over from the big bang, that decompose into high-energy protons with a long halflife, much like radioactive nuclei. There's good evidence for the first part of that statement. Cosmologists call them "dark matter". The other half is speculation.

Re: long live the oh my god particle

obviously the energy amount is not all that relatively huge until you realize its concentrated into a single particle. As more stealing shows, The energy of this particle is some 40 million times that of the highest energy protons that have been produced in any terrestrial particle accelerator.

Obviously, the theory is mostly right --

Re: Obviously, the theory is mostly right --

Well, to be fair, neutrinos dont like to be detected. I think there has only been 1 confirmed detected, extrasolar point source of neutrinos other than the sun, supernova 1987A. "On the average, neutrinos can penetrate four light years of lead before being stopped" So chances of bouncing off a km of ice is pretty low.

Sure, but fusion reactions produce so very, very many of them that the odds are good that some will be detected. Supernova 1987A was 168000 light years away, and despite the phenomally small likelihood of a neutrino from there intersecting a terrestrial neutrino detector, we saw maybe 2 dozen of them.

Gamma ray bursts

Astroboffins only had two theories...

Seems they've forgotten about the synchrotron theory then. The thinking behind this was that cosmic ray particles could acquire their high energies from the electric charge of galaxies. In this scenario, a remote galaxy acts like a _really_ large hadron collider, with particles circling the entire galaxy, and gaining energy as they do so, until they're flipped out, across space, and end up here.